Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions				2 Months Ended	9 Months Ended	12 Months Ended
	Sep. 20, 2023	Jun. 07, 2023	Mar. 04, 2020	Jul. 31, 2023	Sep. 30, 2024	Dec. 31, 2022	Sep. 30, 2023	Jun. 30, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Invested capital contributions					$ 65.0
Accrued dividend rate (in percent)					8.00%
Stockholders' equity, conversion period (in years)					5 years
Common Class A
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common unit, units outstanding (in units)						19,495,376	0	19,495,376
Accrued dividend rate (in percent)			8.00%
Payments of dividends		$ 4.0
Common Class A-1
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common unit, units outstanding (in units)						1,842,520	0	2,281,696
Accrued dividend rate (in percent)			4.00%
Payments of dividends		$ 4.1
Class B Common Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common unit, units outstanding (in units)						4,703,628	0	4,703,628
Class B-1
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Grants in period (in units)				415
Class C
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Temporary equity, redeemable period					5 years
Option to purchase additional units (in shares)		378
Purchase price of additional units (in dollars per share)		$ 26,423
Anti-dilution feature at fair value								$ 1.4
AON Inc.
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stockholders' equity, conversion, threshold volume weighted average price period					30 days
Stockholders' equity, conversion, threshold stock price (in dollars per share) (less than) (greater than)					$ 16.00
AON LLC | Common Class A
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common unit authorized (in units)						19,495,376
Issuance of units (in units)						19,495,376
Common unit, units outstanding (in units)						19,495,376
AON LLC | Common Class A-1
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common unit authorized (in units)						3,000,245
Issuance of units (in units)						1,842,520
Common unit, units outstanding (in units)						1,842,520
AON LLC | Class B Common Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Issuance of units (in units)						5,614,176
Units vested (in units)						4,703,628
Units vested upon consummation of business combination (in units)						910,548
Common Class A
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares issued (in shares)	1,047,343
Stockholders' equity, conversion, threshold volume weighted average price period					5 days
Series A Preferred Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Dividends					$ 2.1
Class A-1 distribution (in shares)	151,610
Stock price (in dollars per share)					$ 10.00
Series A Preferred Stock | Stockholders
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stockholders' equity, conversion period (in years)					5 years
Number of days after five year anniversary					30 days
Stockholders' equity, conversion, threshold volume weighted average price period					30 days
Stockholders' equity, conversion, threshold stock price (in dollars per share) (less than) (greater than)					$ 10.00
Threshold stock price, conversion price adjustment (in usd per share)					$ 5.00
Series A Preferred Stock | AEA Growth Management LP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares issued (in shares)	6,651,610
Series A Preferred Stock | Dividends Paid, Event Prior to June 7, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					125.00%
Series A Preferred Stock | Dividends Paid, Event Prior to June 7, 2025, After June 7, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					120.00%
Series A Preferred Stock | Dividends Paid, Event Prior to June 7, 2026, After June 7, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					115.00%
Series A Preferred Stock | Dividends Paid, Event Prior to June 7, 2027, After June 7, 2026
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					110.00%
Series A Preferred Stock | Dividends Paid, Event Prior to June 7, 2028, After June 7, 2027
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					105.00%
Series A Preferred Stock | Dividends Paid, Event After June 7, 2028
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrued dividend rate (in percent)					100.00%